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herbicide

(Encyclopedia)herbicide hrˈbəsīdˌ [key], chemical compound that kills plants or inhibits their normal growth. A herbicide in a particular formulation and application can be described as selective or nonselectiv...

cochineal

(Encyclopedia)cochineal kŏchĭnēlˈ, kŏchˈĭnēl [key], natural dye obtained from an extract of the bodies of the females of the cochineal bug (Dactylopius confusus) found on certain species of cactus, especial...

Haworth, Sir Walter Norman

(Encyclopedia)Haworth, Sir Walter Norman, 1883–1950, British chemist, Ph.D. Univ. of Göttingen, 1911. Haworth held academic posts at Imperial College of Science and Technology in London (1911–12), the Univ. of...

Erlenmeyer, Richard A. C. E.

(Encyclopedia)Erlenmeyer, Richard A. C. E. ĕrˈlənmīˌər [key], 1825–1909, German chemist. He studied at Giessen under Justus von Liebig and at Heidelberg under Friedrich Kekulé, both German chemists. Erlenm...

Meyerhof, Otto

(Encyclopedia)Meyerhof, Otto ôˈtō mīˈərhōf [key], 1884–1951, American physiologist, b. Germany, M.D. Heidelberg, 1909. He was professor at the Univ. of Kiel (1912–24) and at the Univ. of Berlin and direc...

naranjilla

(Encyclopedia)naranjilla näränhăˈyō [key], large tropical subshrub (Solanum quitoense) of the family Solanaceae (nightshade family), native to the Andes. Tomatolike fruits, orange-colored and leathery-skinned,...

Krebs, Sir Hans Adolf

(Encyclopedia)Krebs, Sir Hans Adolf krĕbz, krĕps [key], 1900–1981, English biochemist, b. Germany, M.D. Univ. of Hamburg, 1925. He taught at Cambridge and at the Univ. of Sheffield and after 1954 was professor ...

Marsh test

(Encyclopedia)Marsh test, method for the detection of arsenic, so sensitive that it can be used to detect minute amounts of arsenic in foods (the residue of fruit spray) or in stomach contents. The sample is placed...

potassium nitrate

(Encyclopedia)potassium nitrate, chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also ...

solder

(Encyclopedia)solder sŏdˈər [key], metal alloy used in the molten state as a metallic binder. The type of solder to be used is determined by the metals to be united. Soft solders are commonly composed of lead an...